When I was doing work on my car a few weeks ago, I noticed that the belt tensioner had what looked like oil dripping from it. It was not motor oil, but something from within that little damper on the tensioner. I had been having problems at higher rpm such as power loss and what seemed like a flat spot. Has anyone else had a tensioner leak like this? It was still holding full tension untill about 5k rpm. Right now my car is still getting the Spec stage 2 clutch, which heat welded itself to the pressure plate, replaced with a factory one.

Anyone know off the top of thier head what a new tensioner runs? Pelican parts and RealOEM didn't show a price.

 

There's oil in there? I thought it was just a spring...

 

On my '04 MCS with 72K miles the tensioner is doing the same thing. I have replaced the belt by myself; how hard is it to replace the tensioner?

 

A new tensioner is a few a few hundred bucks, but I'm fairly sure that there isn't any fluid in them.

 

RealOEM calls it a hydrolic belt tensioner, part number 11287509476. Oh, they want the core back it seems.

The job will be involved. I'll have to take out the airbox, loosten and remove all engine mounts while supporting the engine with a jack, then raise the engine up enough to gain access. Basically, it will be about the same as the s/c pully install. Sounds like fun

 

Yes, there is a strut on the tensioner assembly that is oil filled, as well a spring for proper belt tension. If you see oil coming from the strut, it needs to be replaced as it's only a matter of time before it fails. The tensioner assembly should be replaced around every 50k miles.

Don't let them scare you. I think i payed around $150 for the assembly. You'll have to remove the passenger wheel and inner fender. There are 5 or so bolts to remove. All together it should take close to 2 hours to do yourself. Just make sure you tighten everything back up right. But my timing and needed work could vary i replaced that with a number or other items.

 

I just replaced mine a couple of weeks ago, bought it from Classic, don't think it was much over $150. Did alot of work that day (oil pan gasket etc) but you can get it out w/ the fender liner out. It is a tight fit, and takes some patience.

Good luck.

Nik

 

So would it be possible to replace this without jacking the engine up? For a moment, assume I can access the tensioner bolts. Is there enough space to back them out? I forget the length of those bolts, but there might not be the room to get them fully out.

 

There is room - its just awkward and tight. Its easer if you take the tensioner dampener off.

Nik

 

talk to chadtoolio. he did mine in less than 20 mins at the shop. He did jack up the engine using the car lift. being a bmw club member i think the part was less than 100 bucks at the dealership.

from my experience, mine have only gone bad after a belt snap. it's a good time to add a tentioner stop cable.

 

This is better info ... than lifting the engine.

#1 take off the belt ... FIRST
Remove the tensioner unit
Replace the tensioner unit
use your belt tool to "pin" the tensioner
Install belt
Remove pin

1/2 hour job

 

So then there is space for the bolts to come out. That is good news, but lifting the engine would only take an hour at most.

 

I did the swap on my tensioner for the same reason......belt slipping at high rpm and the damper was shot.

You can get it in and out w/o lifting the engine. It is a bit tight. I just took off the passenger engine mount and just barely lifted the engine to make the install a bit easier.

 

I just undo one nut (for the passenger side mount) and jack the sucker up! The driver side doesn't move much, and there's lots of play in the lower and upper rotational mounts.....

Matt

 

Exactly which nut? The one that connects the bracket on the upper passenger side of the engine to the mount that bolts to the frame rail?

 

I actually took off the bracket/bar that attaches to the mount and the shock tower and then took off the bolt on top of the engine mount. You wouldn't need to take off the bracket as it will move around a bit.

 

My car has polyurethane engine mounts, so any flex you speak of is non-existant.

ScottinBend, was there enough room to get a torque wrench in there when you did it your way?

 

Not for all 4 of the bolts. But then again I didn't remove the fender liner either. I just put a bit of blue locktite on them and tightened them up.

 

Also I have found that this lifts it at a angle that almost makes it more difficult ...

 

I'm inclined to just jack the engine up and do it right with a torque wrench. It will be a fun saturday project in a few weeks.